@article{duarte_yadav_castorena_2024, title={Using Color Measurements to Quantify Aggregate and Asphalt Emulsion Compatibility}, volume={5}, ISSN={["2169-4052"]}, url={https://doi.org/10.1177/03611981241242754}, DOI={10.1177/03611981241242754}, abstractNote={The compatibility of asphalt emulsion and aggregate plays a significant role in the aggregate retention performance of chip seals. There are several, similar standardized test methods available for assessing the compatibility of emulsion–aggregate blends, including AASHTO T 59, ASTM D244, and North Carolina Department of Transportation (NCDOT) A-24. In all methods, a sample of aggregate and emulsion is mixed and rinsed. Subsequently, the compatibility of the rinsed sample is reported as “good,”“fair,” or “poor” based on visual inspection of asphalt coating the aggregate surface area. These visual inferences are subjective, making them susceptible to potential operator bias. The aim of this study is to develop an objective means to quantify emulsion–aggregate compatibility by using the Asphalt Compatibility Tester to obtain color-based measures in lieu of the visual assessment procedures. Multiple aggregate sources (granite, limestone, and lightweight), emulsion types (CRS-2L, CRS-2, and SS-1h), and sources were evaluated. In total, 25 emulsion–aggregate blends were analyzed. The results were used to establish color index thresholds to capture good- versus fair- or poor-performance emulsions. Additionally, chip seal samples from five construction projects were subjected to the Vialit test to measure aggregate retention performance. The Vialit test results were compared with the compatibility test results as a preliminary evaluation of the color-based criteria proposed here. The results indicated that the NCDOT A-24 procedure coupled with color measurements is effective at capturing the compatibility of emulsion–aggregate blends, providing a potential means to remove the subjectivity of the current visual rating procedures.}, journal={TRANSPORTATION RESEARCH RECORD}, author={Duarte, Gabriel Macedo and Yadav, Shivpal and Castorena, Cassie}, year={2024}, month={May} }
 @article{rashetnia_kusam_yadav_pour-ghaz_tayebali_2022, title={Quantifying moisture damage in asphalt concrete using axisymmetric flexural vibration technique}, volume={23}, ISSN={["1477-268X"]}, DOI={10.1080/10298436.2020.1757671}, abstractNote={ABSTRACT The Tensile Strength Ratio (TSR) test is commonly used to quantify the moisture susceptibility of asphalt mixtures. This test method is based on the indirect tensile strength, which is not a fundamental property and hence cannot be used in the asphalt mixture design process. Therefore, alternative test methods that use a fundamental property to quantify moisture sensitivity of asphalt mixtures are needed. This study investigates if the linear impact resonance shift and frequency spectrum bandwidth changes measured using Axisymmetric Flexural Vibration (AFV) technique can be used to quantify moisture damage. This test enables calculation of the dynamic elastic modulus of the disk, based on measured resonance frequency as well as quantification of vibration energy dissipation in the specimens based on the change in bandwidth of frequency spectrum. AFV test is used to quantify moisture damage susceptibility of asphalt mixture specimens with different moisture conditioning levels and different mixture designs. The results of the AFV test are compared with the TSR test. Also, the sensitivity of the AFV test to quantify the effect of thixotropic aging due to storage and temperature are discussed. The results show that the AFV technique can successfully quantify moisture damage and the effect of aging and temperature change.}, number={3}, journal={INTERNATIONAL JOURNAL OF PAVEMENT ENGINEERING}, author={Rashetnia, Reza and Kusam, Abhilash and Yadav, Shivpal and Pour-Ghaz, Mohammad and Tayebali, Akhtarhusein}, year={2022}, month={Feb}, pages={523–535} }
 @article{yadav_kusam_tayebali_2021, title={Evaluating Moisture Damage Using Impact Resonance Test}, volume={49}, ISSN={["1945-7553"]}, DOI={10.1520/JTE20200372}, abstractNote={Abstract}, number={6}, journal={JOURNAL OF TESTING AND EVALUATION}, author={Yadav, Shivpal and Kusam, Abhilash and Tayebali, Akhtarhusein A.}, year={2021}, month={Nov}, pages={4118–4134} }